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US5744194A - Process and device for coating at least one optical waveguide - Google Patents

Process and device for coating at least one optical waveguide Download PDF

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Publication number
US5744194A
US5744194A US08/666,395 US66639596A US5744194A US 5744194 A US5744194 A US 5744194A US 66639596 A US66639596 A US 66639596A US 5744194 A US5744194 A US 5744194A
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US
United States
Prior art keywords
optical waveguide
filling
filling compound
wiping device
bypass
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US08/666,395
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English (en)
Inventor
Thomas Muller
Frank Renner
Wilfried Reissenweber
Reiner Schneider
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Assigned to SIEMENS AKTIENGESELLSCHAFT reassignment SIEMENS AKTIENGESELLSCHAFT ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MULLER, THOMAS, REISSENWEBER, WILFRIED, RENNER, FRANK, SCHNEIDER, REINER
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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
    • G02B6/4479—Manufacturing methods of optical cables
    • G02B6/4483—Injection or filling devices

Definitions

  • the invention relates to a process for coating at least one optical waveguide with a filling compound with the coating being undertaken in at least two successive filling stages and part of the filling compound being wiped off by means of a wiping device of reduced cross section between the filling stages.
  • a process of this kind is disclosed by EP 0 532 999.
  • the filling compound is fed to a first filling chamber which is connected to a second filling chamber via a passage nozzle for the optical waveguide (or the optical waveguide bundle).
  • This second filling chamber is located offset or upstream from the first filling chamber in a direction opposite or counter to the passage direction, of the waveguide and is connected to the first filling chamber via a bypass.
  • a wiping off of the filling compound takes place, which is achieved by means of a correspondingly reduced cross section of the passage nozzle.
  • the position which the optical waveguide assumes inside the filling compound is not more closely defined, since the second filling stage has an outlet opening which is as large as is required by the desired material thickness of the filling compound.
  • the invention is based on the object of configuring the filling process to be as effective as possible and of ensuring a largely defined position of the optical waveguide within the filling compound. This object is achieved in the case of a process of the type mentioned at the outset by a proportion of the filling compound which is wiped off in the region of the wiping device being led past the optical waveguide via a bypass in the passage direction or direction of movement of the wavguide and subsequently being fed once more to coat the coated optical waveguide in the second filling stage.
  • the bypass according to the invention represents a bridging over of the wiping device, that is to say part of the filling compound moves in the bypass in the same direction as the already coated optical waveguide (that is to say, in the passage direction).
  • a proportion of the filling compound is subsequently fed once more, specifically to the partially coated optical waveguide which is defined in terms of its position by the wiping device, in particular is centered.
  • the invention relates furthermore to a device for carrying out the process according to the invention, which is characterized in that a bypass is provided in the region of the wiping device, through which bypass a proportion of the filling compound which is wiped off can be led past the wiping device.
  • FIG. 1 is a longitudinal cross sectional view of a filling device, operating in accordance with the process of the present invention
  • FIG. 1A is a transverse cross sectional view of a waveguide produced according to the present invention.
  • FIG. 2 is an enlarged longitudinal cross sectional view of the wiping device and bypass according to FIG. 1;
  • FIG. 3 is an end view of the left end of the wiping device of FIG. 2;
  • FIG. 4 is a cross sectional view taken on lines IV--IV of FIG. 2;
  • FIG. 5 is an enlarged longitudinal cross sectional view of another embodiment of the wiping device.
  • FIG. 6 is an end view of the right end of the wiping device of FIG. 5.
  • a filling device containing two filling stages FS1 and FS2, is provided for the production of an optical waveguide strand LA (FIG. 1A) and at least one optical waveguide LW is fed to the device.
  • an optical waveguide LW is fed through a bore B1 of an entry nozzle BD, of a prefilling stage, which nozzle ED is followed by two independent filling chambers FSK1 and FSK2.
  • a filling compound FM is fed to the filling chamber FSK2, lying downstream as seen in the passage direction.
  • Part of this filling compound FM passes via a bypass BP from the downstream filling chamber FSK2 into the first or upstream filling chamber FSK1, that is to say in the bypass BP the filling compound flows counter to the passage direction of the optical waveguide LW which is moved through a bore B2 of a guide nozzle FSD of reduced cross section.
  • This filling device containing two chambers, are described in more detail in the already mentioned EP 0 532 999.
  • an elongated guide tube FR which has in its interior a first (larger) bore BO1 and an adjoining (smaller) bore BO2, through which the optical waveguide LW is led, is screwed via a thread GW1 into the outer wall of the filling chamber FSK2.
  • the guide tube FR has an attachment FA fitted to the front end thereof, which is shown enlarged in FIG. 2.
  • the guide tube FR reaches into the interior of an extruder head SK, which is described in greater detail in EP 534 208.
  • the extruder head SK provides for the application of a double protective sleeve to the optical waveguide LW coated with filling compound and, the compounds M1 and M2, which are necessary for this double layer sleeve are led via ducts KA1 and KA2.
  • Adjoining the duct KA1 is an annular groove RN1.
  • the compounds M1 and M2 pass via gaps SP11 and SP21 to guide ducts SP21 and SP22, running obliquely, between which there extends a web ST12. Subsequently, both compounds meet in a common conical duct SPG which ends in a bore BO.
  • the outer diameter of this bore BO fixes the outer diameter of the sleeve SH of the optical waveguide strand LA to be produced.
  • the protective sleeve SH is of a two-layer is and being formed from the materials M1 and M2 by coextrusion.
  • the extruder head SK is composed of a heater HE and various guide elements FK1 (lying on the inside) and FK2 and FK3 (lying on the outside), and is held together by screw fixings VS1 and VS2.
  • the common exit duct SPG is bounded on the outside by a wall DK and on the inside by a mandrel DO, which has a continuous bore into which the guide tube FR extends.
  • the filling process itself runs in such a manner that the filling compound FM is first led both into the filling chamber FSK2 and, via the bypass BP operated in countercurrent, into the filling chamber FSK1.
  • a wetting or coating, which is reliable and carried out on all sides, of the optical waveguide LW (or of the optical waveguide bundle) is guaranteed with, air inclusions largely being avoided.
  • the optical waveguide LW thus coated next passes into the bore BO1 of the guide tube FR, a certain centering and wiping effect already occurring as a result of the reduction in the cross section of the bore BO1 in comparison with the size of the filling chamber FSK2.
  • a renewed wiping effect and an additional improvement of the coating or wetting of the optical waveguide LW with the filling compound occurs as a result of the second bore B02 which has a reduced cross section and is located downstream.
  • the optical waveguide LW is guided by means of the small diameter of the small bore BO2 in a specific manner in terms of waveguide location, which could not be achieved in the case of correspondingly large bore cross sections.
  • the details of the construction in the region of the wiping device AE according to FIG. 1 can be seen from the enlarged cross sectional representation of FIG. 2.
  • the attachment FA is screwed into the interior of the guide tube FR, a sleeve-like extension FAB extending slightly into an end of the interior of the tube FR.
  • an entry opening FEO of conical design which merges into the bore BO31, which has a diameter which is greatly reduced in comparison with the bore BO2.
  • the opening angle is expediently approximately 15° to 45°.
  • the bore BO31 in the sleeve-like extension FAH serves as a wiping device AE, and the bore BO31 is selected to be only a little larger than the outer diameter of the optical waveguide LW or of any optical waveguide bundle.
  • a very small but exactly defined quantity of the filling compound is still present on the optical waveguide or optical waveguide bundle; however, this quantity of the filling compound is not sufficient, for the desired cushioning effect within the strand sleeve SH.
  • the bypass BY is provided, which initially has the form of a cylindrical gap ZS.
  • This cylindrical gap ZS merges at its end via obliquely running individual bores BR1 to BRn, which are arranged in a crown shape, into the interior of the attachment FA, and the filling compound is fed once more to the coated optical waveguide LW at the end of the calibration bore BO31.
  • FIG. 4 shows a cross section extending at right angles to the longitudinal axis of the attachment FA in the region of the oblique bores BR1 to BRn.
  • the number of these obliquely or radially extending bores BR1 to BRn is selected to correspond to the additional filling compound feed.
  • the quantity of the filling compound which is fed can be set by the diameter of these oblique bores BR1 to BRn.
  • the following bore BO32 is of an enlarged diameter, specifically expediently enlarged to 1 to 2 times the diameter of the previous calibration bore BO31.
  • the filling space thus additionally produced is filled up by the filling compound proportion fed via the bypass BY, and the optical waveguide LW, in the further course of the attachment FA, is exactly centrally embedded, that is to say at a location predetermined and defined by the calibration bore BO31, within the filling compound.
  • the attachment FA has expediently a tubular extension FAR (internal diameter likewise BO32) on its output side. In this case, this extension, as can be seen from FIG.
  • the attachment FA is guided in the interior of the mandrel DO the extruder head SK and rests by means of webs FZA which are directed outward in the shape of a web (see FIG. 3, which shows a front view of the attachment FA, seen in the direction of the entry opening FEO) on the inner wall of the mandrel DO.
  • a corresponding insulating layer can also be applied as an additional heat insulation, for example to the inner wall of the mandrel DO.
  • the extruded protective sleeve SH is pulled down at the output of the injection nozzle BO to the outer diameter of the tubular extension FAR and is therefore applied to the outer layer of the filling compound FM in a manner which is free of air and gaps.
  • water repellent compounds preferably containing oil components, are used as filling compounds. These expediently have thixotropic and/or thickening agents added to them.
  • the invention provides the possibility of carrying out a filling or coating process which is trouble-free, continuous and operates surely and reliably, for the filling compounds in the production of so-called hollow strands ("loose tubes").
  • the invention can be used in the case of single and multiple component compounds, compressible compounds, etc., that is to say it can be applied irrespective of the construction and composition of the filling compounds.
  • the invention makes it possible to realize high passage speeds, for example of the order of magnitude of more than 100 m/min, and supplies optical waveguides or optical waveguide bundles which are positioned exactly centrally in the interior of the protective sleeve SH.
  • Filling compound strands which are applied severely eccentrically can for example bring out disturbances in that the optical waveguide LW sticks to the inner wall of the extruded plastic sleeve during contraction.
  • any alignment errors in the passage direction of the optical waveguide LW and, for example, spatial deviations of individual components, for example of the extruder head SK with respect to the coating device VF are uncritical, since as a result of the wiping device AE and the bypass BY, any alignment errors are eliminated once more.
  • a completely axially accurate alignment of all the elements of the filling device is thus not absolutely necessary.
  • the wiping device AE at a specific distance after the prefilling device VF, specifically expediently at a distance of between 10 and 200 mm (corresponding approximately to the length of the tube FR).
  • FIG. 5 shows an attachment FA* of modified design which, just as shown in the same way in FIG. 1, can be screwed into the guide tube FR at the outlet side end of the latter.
  • a centrally extending bore BO*31 is provided in the center, which (like BO31 in FIGS. 1 and 2) serves as a calibration nozzle and accommodates the optical waveguide LW or an optical waveguide bundle.
  • Arranged on a part circle are n bores BR*1 to BR*n, which extend parallel to the central bore BR*31.
  • These bores BR*1 to BR*n form the bypass for the wiped-off excess filling compound and the attachment FA* thus likewise represents a wiping device in contrast to the bore BO2 of the guide tube FR.
  • the bores B1, B2 and BO31 are selected to be only a little larger (expediently around 5-25%) than the outer diameter of the respective optical waveguide can be at a maximum (that is to say taking into account diameter fluctuations).
  • the most central arrangement possible of the optical waveguide LW inside the protective sleeve SH of the optical waveguide strand LA can be achieved therewith.
  • the bore BO1 has an internal diameter which is expediently between 1.5 and 3 times the maximum outside diameter of the optical waveguide LW.
  • the bore BO2 is selected to be larger than the bore BO31 of the wiping device AE and can expediently be selected between 1.3 and 2 times the outer diameter of the optical waveguide LW. In this range, by means of the application of a corresponding pressure, there results the advantageous possibility of achieving for the filling compound FM a higher flow speed (as a result of the small cross section of the bore BO2), which leads to a specific carrying-along effect occurring for the optical waveguide LW as a result of the greater (in contrast with the passage speed of LW) flow speed of the filling compound FM.
  • the bore BO32 finally fixes the proportion of the filling compound FM within the protective sleeve SH and is therefore to be selected corresponding to the requirements on the respective optical waveguide strand LA.
  • the bore BO32 and the bore BO2 are expediently selected to be approximately equally large. Since the bore BO31 is expediently virtually completely closed by the optical waveguide or the optical waveguide bundle, BO2 is expediently selected to be about as large as BO32.
  • the bore B1 and the bore B2, as well as the bore BO31, are selected such that the respective optical waveguide bundle can just be moved easily through the respective opening without seriously rubbing on its inner wall in each case.
  • the dimensioning of the bore BO2 can, as already mentioned above under a), be used in the generation of a thrust force on the optical waveguide bundle, by selecting a correspondingly narrow cross section, if this cross section is reduced by comparison with that of the bore BO1. As a result, there occurs a greater filling mass speed than the actual passage speed of the optical waveguide bundle, and a type of carrying-along effect is produced.
  • each of the oblique bores can be closed or opened, for example with a corresponding pin to be driven externally, as a result of which a fine metering of the eccentric arrangement of the optical waveguide within the protective sleeve can be carried out.
  • it can also be sufficient to make, for example, each second or third oblique bore able to be closed with a corresponding pin.
  • the pins for example PI1, PI2 etc.
  • the pins are activated one after another in the peripheral direction, there results a displacement of the optical waveguide into various positions in relation to the longitudinal axis of the optical waveguide strand and thus, as a whole, an approximately helical course of the optical waveguide within the protective sleeve.
  • a helical course of this type of the optical waveguide or of the optical waveguide bundle is particularly expedient if a relatively large percentage of excess length is desired.
  • Such an eccentric incorporation of optical waveguides in an exactly defined manner is incidentally also possible by the attachment FA having a bore BO31 and BO32 which runs eccentrically, and the attachment FA is arranged as a whole so as to be rotatable within the mandrel DO.
  • an eccentrically fitted calibration bore BO31 produces an exactly defined helical course for the optical waveguide the optical waveguide bundle LW within the filling pound FM.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Surface Treatment Of Glass Fibres Or Filaments (AREA)
  • Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
  • Optical Couplings Of Light Guides (AREA)
US08/666,395 1993-12-23 1994-12-20 Process and device for coating at least one optical waveguide Expired - Fee Related US5744194A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE4344250A DE4344250A1 (de) 1993-12-23 1993-12-23 Verfahren und Vorrichtung zum Beschichten mindestens eines Lichtwellenleiters
DE4344250.1 1993-12-23
PCT/DE1994/001511 WO1995017694A1 (de) 1993-12-23 1994-12-20 Verfahren und vorrichtung zum beschichten mindestens eines lichtwellenleiters

Publications (1)

Publication Number Publication Date
US5744194A true US5744194A (en) 1998-04-28

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US08/666,395 Expired - Fee Related US5744194A (en) 1993-12-23 1994-12-20 Process and device for coating at least one optical waveguide

Country Status (7)

Country Link
US (1) US5744194A (fi)
EP (1) EP0736193B1 (fi)
AT (1) ATE158871T1 (fi)
CA (1) CA2179751A1 (fi)
DE (1) DE4344250A1 (fi)
FI (1) FI962530L (fi)
WO (1) WO1995017694A1 (fi)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060028587A1 (en) * 2004-08-05 2006-02-09 Peng Juen T TV tuner
JP2009116240A (ja) * 2007-11-09 2009-05-28 Fujikura Ltd ルースチューブの押出成形方法及びその装置、並びに前記押出成形方法から得られたルースチューブ
CN105093453A (zh) * 2015-08-31 2015-11-25 沈阳亨通光通信有限公司 一种光纤套塑引导装置
CN112099167A (zh) * 2020-09-27 2020-12-18 江苏亨通光电股份有限公司 松套管双预填充充油装置及工艺
CN115685466A (zh) * 2022-11-14 2023-02-03 长飞光纤光缆股份有限公司 一种中心束管气吹微缆、挤出模具及制备方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19719220C2 (de) * 1997-05-07 1999-09-16 Troester Maschf Paul Querspritzkopf einer Extrusionsanlage
US6207260B1 (en) 1998-01-13 2001-03-27 3M Innovative Properties Company Multicomponent optical body

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0087757A1 (de) * 1982-02-26 1983-09-07 Siemens Aktiengesellschaft Einrichtung zur Herstellung eines elektrischen und/oder optischen Kabels
EP0255686A2 (de) * 1986-07-31 1988-02-10 Siemens Aktiengesellschaft Verfahren zur Herstellung eines gefüllten optischen Übertragungselementes und Einrichtungen zur Durchführung des Verfahrens
EP0532999A1 (de) * 1991-09-18 1993-03-24 Siemens Aktiengesellschaft Vorrichtung zum Füllen der Zwischenräume eines Kabels
EP0534208A1 (de) * 1991-09-23 1993-03-31 Siemens Aktiengesellschaft Spritzkopf für die Coextrusion von mindestens zwei Kunststoffmaterialien

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0087757A1 (de) * 1982-02-26 1983-09-07 Siemens Aktiengesellschaft Einrichtung zur Herstellung eines elektrischen und/oder optischen Kabels
US4474638A (en) * 1982-02-26 1984-10-02 Siemens Aktiengesellschaft Device for manufacturing electrical and optical cables
EP0255686A2 (de) * 1986-07-31 1988-02-10 Siemens Aktiengesellschaft Verfahren zur Herstellung eines gefüllten optischen Übertragungselementes und Einrichtungen zur Durchführung des Verfahrens
US4810429A (en) * 1986-07-31 1989-03-07 Siemens Aktiengesellschaft Method and apparatus for the manufacture of filled optical transmission elements
EP0532999A1 (de) * 1991-09-18 1993-03-24 Siemens Aktiengesellschaft Vorrichtung zum Füllen der Zwischenräume eines Kabels
EP0534208A1 (de) * 1991-09-23 1993-03-31 Siemens Aktiengesellschaft Spritzkopf für die Coextrusion von mindestens zwei Kunststoffmaterialien

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060028587A1 (en) * 2004-08-05 2006-02-09 Peng Juen T TV tuner
JP2009116240A (ja) * 2007-11-09 2009-05-28 Fujikura Ltd ルースチューブの押出成形方法及びその装置、並びに前記押出成形方法から得られたルースチューブ
EP2219061A1 (en) * 2007-11-09 2010-08-18 Fujikura, Ltd. Extrusion method of loose-type tube and its device, and loose-type tube
US20100247045A1 (en) * 2007-11-09 2010-09-30 Naoki Okada Method for extrusion-molding loose tube and apparatus therefor, and loose tube
EP2219061A4 (en) * 2007-11-09 2012-05-09 Fujikura Ltd METHOD FOR EXTRUDING LOW-TYPE TUBE AND ITS DEVICE, AND LOW-TYPE TUBE
US8470213B2 (en) 2007-11-09 2013-06-25 Fujikura Ltd. Method for extrusion-molding loose tube and apparatus therefor, and loose tube
US9056434B2 (en) 2007-11-09 2015-06-16 Fujikura Ltd. Method for extrusion-molding loose tube and apparatus therefor, and loose tube
CN105093453A (zh) * 2015-08-31 2015-11-25 沈阳亨通光通信有限公司 一种光纤套塑引导装置
CN105093453B (zh) * 2015-08-31 2019-03-29 沈阳亨通光通信有限公司 一种光纤套塑引导装置
CN112099167A (zh) * 2020-09-27 2020-12-18 江苏亨通光电股份有限公司 松套管双预填充充油装置及工艺
CN115685466A (zh) * 2022-11-14 2023-02-03 长飞光纤光缆股份有限公司 一种中心束管气吹微缆、挤出模具及制备方法
CN115685466B (zh) * 2022-11-14 2023-12-19 长飞光纤光缆股份有限公司 一种中心束管气吹微缆及制备方法

Also Published As

Publication number Publication date
EP0736193B1 (de) 1997-10-01
DE4344250A1 (de) 1995-06-29
WO1995017694A1 (de) 1995-06-29
EP0736193A1 (de) 1996-10-09
ATE158871T1 (de) 1997-10-15
FI962530A0 (fi) 1996-06-18
CA2179751A1 (en) 1995-06-29
FI962530L (fi) 1996-06-18

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Owner name: SIEMENS AKTIENGESELLSCHAFT, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MULLER, THOMAS;RENNER, FRANK;REISSENWEBER, WILFRIED;AND OTHERS;REEL/FRAME:008083/0124

Effective date: 19941206

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Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

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Effective date: 20020428